ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1966.tb00439.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

A grazing experiment to measure the feeding values of 4‐week‐old regrowths of S37 cocksfoot, S23 ryegrass and S24 ryegrass is described. A low grazing pressure was maintained on the pastures to ensure that animal production was not limited by herbage availability. Each sward was grazed by a group of 12 lambs under “worm‐free” conditions. Increases in empty body weight, dry body weight and energy were measured by the comparative slaughter technique.The liveweight gain of the cocksfoot‐fed lambs was the same as the ryegrass‐fed groups during the first half of the experiment but was lower in August and September. The final liveweight gains on S23 and S24 ryegrass were 14% higher than on S37 cocksfoot, but in terms of energy retention S23 ryegrass was 18% and S24 7% better than S37 cocksfoot. Digestibility measurements of herbage cut from the plots being grazed showed a positive correlation with energy retention by the lambs. Energy retention was negatively correlated with the proportion of acetic acid in the rumen adds, a fraction which was itself correlated with the soluble carbohydrate content of the herbage, but not with the digestibility of the herbage.When interpreting animal‐production results, intake, digestibility and rumen volatilc‐fativ‐acid proportions, should be taken into account. Because of the inadequacy of present methods of estimating the herbage intake of grazing animals, measurement of body‐energy gains is not justified and empty‐liveweight gains are sufficiently precise to measure relative energ

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1966.tb00440.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

The results of experiments undertaken in England and New Zealand are reported. Under highly productive pasture a significant correlation was found between pasture production and earthworm numbers and weights. This relationship was not evident until the pastures were more than 3 years old. On pastures of similar total dry‐matter production there was a significant correlation between yield of clover and numbers and weights of earthworms. The return of dung by the grazing animal increased earthworm numbers and weights, and the application of nitrogenous fertilizer had a similar but less marked effect. The earthworm population was not demonstrably related to the macro‐organic‐maller content of the pastures. The grazing of grass‐clover pastures was not essential for an increase in earthworm populations to occur.Allolohophoraspecies (mainlyA. caliginosa) were dominant under pure grass swards, whereasLumhricusspecies (mainlyL. rubellus) were dominant under grass/clover

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1966.tb00441.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

An account is given of the production and use of grass in Lancashire, including statistical information relating to acreages and livestock numbers in June, 1963; a map shows the distribution of grassland in the county as percentages of the agricultural area. For convenience the county is divided into 5 areas, each with different farming systems. Reference is made to the Ministry of Agriculture's Experimental Husbandry Farm and its influence on farming in the surrounding districts in East Lancashire.

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1966.tb00442.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1966.tb00443.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

Families ofDactytis g/omerataandLolium perennederived from ripe inflorescences collected in western France over a range of nearly 7° of latitude were grown at Aberystwyth, 52° N lat. Their growth was examined to determine whether latitude and the habitat of the collected families affected the dates of ear emergence, phml form, and height of the flowering shoots when the grasses were grown at Aberystwyth, Ear emergence was found to be delayed as the latitude of the seed source increased, irrespective of the year of sowing, or, in the case of cocksfoot, irrespective of whether the plants were in their first or second harvest year.Plant growth‐form and panicle height were recorded only for the cocksfoots, and the results indicate that they were influenced by habitat and that they reflected the intensity of biotic control that had operated.The families derived from meadows or road verges tended to contain a higher percentage of erect tall types. When, however, the seeds came from grazed orchards or pastures, there were few or no erect plants, but many with a more or less prostrate habit and shorter panic

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1966.tb00444.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

Three comparisons were made, with non‐lactating fistulated cows, of the voluntary intake of silage and hay prepared from similar herbage. On average 28% more dry matter was eaten as hay than as silage. Silage and hay had similar digestibilities, but silage residues tended to remain in the gut longer than those of hay. The amount of digesta in the reticulo‐rumen immediately after a mealad lib. was greater with hay than with silage. The cows spent longer eating and ruminating per kg dry matter of silage than of hay. The results are discussed in relation to possible factors determining the voluntary intake of sil

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1966.tb00445.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

An experiment is described in which the liveweight gains of cattle, grazing different pasture species, were measured when grazing sequences were arranged in the form of a Latin Square. The average coefficient of variation for the 6 “animal” Latin squares used was 28·5%, with a range of 15·1 to 42·6%. Significant improvements in liveweight gain were demonstrated arising from the inclusion ofStylosanthes gracilisin swards ofChloris gayanaandPanicum maximum.The problems of conducting and interpreting trials of this type are discussed in relation to the need for data on the economic value of pasture species in the tropics. Latin square grazing designs offer a useful means of measuring animal production from pasture, with the advantage of requiring relatively small numbers of animals in each trial, but trials should be repeated at different

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1966.tb00446.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

The grazing of 3 relatively productive grasslands (Festucaf Agrostis) by hill sheep was examined in relation to herbage consumption, grazing pressure, dung deposition and the number of sheep in the area. Herbage intake ranged from 400 Ib/ac/annum (dry weight) on the highest (2450 ft O. D.) and most exposed grassland to 800 Ib/ac/annum on a grassland (1700 ft O. D.) adjacent to extensive heather moorland on blanket bog. The highest pressure (5·5 sheep/ac) was also found on grassland surrounded by blanket bog (1 sheep/14 ac)

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1966.tb00447.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1966.tb00448.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY